Jack post

ABSTRACT

A jack post constructed from component parts which can be readily disassembled to be adjustable to accommodate different floor heights in a construction site comprises a tubular base section, a nut, mounting means for mounting the nut on the base section with its threaded passage aligned with the longitudinal axis at the base section, a threaded stem threadedly engaging the threaded opening in the nut, a rigid shank projecting upwardly from the nut, a tubular guide section supported by the nut and adapted to contain and guide the shank in aligned driving engagement with the threaded stem whereby rotation of the nut with respect to the threaded stem causes longitudinal movement of the shank with respect to the tubular base to extend or contract the jack post as required. The rigid shank is removable so as to be replaced by rigid shanks of various lengths as required to adjust the overall length of the jack post for different applications.

United States Patent [1 1 Elias [4 1 Nov. 18, 1975 JACK POST [75] Inventor: Murray A. Elias, lslington, Canada [73] Assignee: Dell Holdings Limited, Toronto,

Canada 221 Filed: Jan. 17, 1975 211 App]. No.: 541,705

Primary Examiner-Othell M. Simpson Attorney, Agent, or Firm-Fetherstonhaugh & Co.

1 5 7 1 ABSTRACT A jack post constructed from component parts which can be readily disassembled to be adjustable to accommodate different floor heights in a construction site comprises a tubular base section, a nut, mounting means for mounting the nut on the base section with its threaded passage aligned with the longitudinal axis at the base section, a threaded stem threadedly engaging the threaded opening in the nut, a rigid shank projecting upwardly from the nut, a tubular guide section supported by the nut and adapted to contain and guide the shank in aligned driving engagement with the threaded stem whereby rotation of the nut with respect to the threaded stem causes longitudinal movement of the shank with respect to the tubular base to extend or contract the jack post as required. The rigid shank is removable so as to be replaced by rigid shanks of various lengths as required to adjust the overall length of the jack post for different applications.

4 Claims, 5 Drawing Figures US. Patent Nov. 18, 1975 Sheet 1 of2 3,920,220

US. Patent Nov. 18,1975 Sheet20f2 3,920,220

JACK rosr This invention relates to jack posts. In particular, this invention relates to a jacking post suitable for use in the construction industry in applications such as support posts for construction safety fences.

Jack posts are used extensively in the construction industry to extend between adjacent floors of a building under construction. The jack posts may be used to support an overhead member or as a support for a construction safety fence. The distance between floors in the construction of a building may vary widely, distances in the range of 7 feet 6 inches to 16 feet being quite common. Because of the very large variation in the distance between adjacent floors, it is common practice to maintain a stock of jack posts of various lengths. It has not previously been possible to provide a jack post which was adjustable in length to accommodate the wide variation in floor heights. As a result, a costly inventory of jack posts of various lengths must be maintained.

The present invention overcomes the difficulties of the prior art defined above and provides a strong jack post which is formed from parts which can be readily disassembled and which includes parts which can be supplied in different lengths to accommodate the different floor heights.

According to an embodiment of the present invention, there is provided a jack post which is capable of being disassembled and which comprises a tubular base section, a nut, a mounting means for mounting the nut on the base section, a threaded stem threadedly engaging the nut, a rigid shank, a tubular guide section supported at one end by the nut and adapted to contain and guide the rigid shank in aligned driving engagement with the threaded stem whereby rotation of the nut with respect to the threaded stem causes longitudinal movement of the shank with respect to the tubular base.

The invention will be more clearly understood with reference to the following detailed specification read in conjunction with the drawings.

FIG. 1 is a pictorial view illustrating the manner in which a safety construction fence is mounted on safety fence posts according to an embodiment of the present invention;

FIG. 2 is an enlarged detailed view illustrating the manner in which the operating means of the safety fence posts engages the safety fence panel;

FIG. 3 is a longitudinal sectional view through a safety fence post according to an embodiment of the present invention;

FIG. 4 is an enlarged detailed view of the jacking screw component of the fence post; and

FIG. 5 is a partially sectioned pictorial view of the turn-buckle mechanism of the fence post.

In the embodiment of the invention illustrated in FIG. 1 of the drawings, the fence posts are of the floor to floor type and have feet 12 at opposite ends thereof engaging floors 14 of a construction site. The feet 12 are movable towards and away from one another in response to rotation of turn-buckle 18. The turn-buckle 18 has diametrically oppositely opposed fence mounting brackets 16 extending outwardly therefrom. The upper rail 20 of a conventional safety fence panel 22 rests on the support bracket 16 and when the fence is in this position, it is impossible to move the support brackets 16 in a manner which would permit the adjustment of the length of the safety fences.

As shown in FIG. 5 of the drawings, the turn-buckle member 18 consists of a tubular guide section 24 having a nut 26 located substantially centrally of the length thereof. The nut 26 is secured within the tubular guide section 24 by welding or the like. The brackets 16 are also preferably secured to the nut 26. The opposite ends of the tubular guide section 24 are of reduced diameter so as to extend in a close fittingrelationship with respect to the telescoping tubular members which form the jacking post as will be described hereafter. The ends of the tubular guide section 24 are reinforced by rings 28. The nut 26 has a threaded passage 30 opening therethrough which is adapted to receive the threaded stem 32 of the jacking rod 34 (FIG. 4). The jacking rod 34 has an enlarged head portion 36 at the upper end thereof upon which a compression spring 38 rests.

To assemble the jack post to the configuration shown in FIG. 3 of the drawings, the threaded stem 32 is mounted within the threaded passage 30 of the nut 26 of the turn-buckle 18. This assembly is then located in a position wherein the nut 26 rests on the upper end face 42 of a tubular base section 40. The tubular guide section 24 thusserves to mount the nut on the base section with the threaded passage 30 aligned with the longitudinal axis of the base section 40. A tubular sleeve section 44 is located within the upper end of the tumbuckle l8 and has a lower end 46 resting on the upper surface of the nut 26. A rigid shank member 48 has a lower end 50 resting on the upper end of the spring 38.

In use, the post 10 is vertically oriented between spaced floors and the turn-buckle 18 may be manually rotated by engaging the brackets 16. Rotation of the turn-buckle 18 causes rotation of the nut 26 which in turn drivesthe stem 32 and its associated head 36 upwardly with respect to the tubular base member 40. The rigid shank member 48 is driven upwardly by the spring 38 into engagement with the upper floor. The turn-buckle 18 is rotated until the upper foot 12 engages the upper floor 14 to a sufficient extent to at least partially compress the compression spring 38. When the brackets 16 are rotated to a position in which they may engage the top rail 20 of the fence 22. The top rail 20 of the fence 22 rests on a pair of brackets 16. When the top rail 20 is in this position, it is impossible to move the bracket 16 and consequently it is impossible to move the turn-buckle 18. This interlocking relationship between the brackets 16 and the fence 22 serves to prevent tampering with the assembly. The compression spring 38 is important in this type of apparatus as it ac.-.

commodates variations in the floor height resulting from expansion and contraction in the structure due to changing climatic conditions.

When the jack post is to be used in an application where the length of the post must be adjusted beyond the range of the jacking screw the rigid stem 48 is removed from its position disposed within the tubular sleeve section 44 and a longer or a shorter shank is substituted therefor as required. By reason of the fact that the rigid shank is not permanently secured with respect to any of the components of the jack it is a simple matter to remove the shank 48 by withdrawing it through the open end of the tubular sleeve section 44. A stock of rigid shanks of various lengths is all that need be maintained in order to provide a wide range of lengths of jacking posts. When a very long shank 48 is to be used the tubular sleeve section 44 serves. to add,

strength to the jack post asit serves to restrain the rigid shank against lateral movement. lttwill be understood that whereas a substantial clearance is shown in the drawings between the shank 48 and the tubular sleeve section. The clearance provided in practice is merely sufficient to permit the shank to move in a close fitting sliding relationship within the tubular sleeve section 44. Various modifications of the device of the present invention will be apparent to those skilled in the art with- V out departing from the scope of the invention.

For example, the guide section 24 of the tum-buckle may be extended to. replace the tubular sleeve section 44 in applicationswhere a long sleeve section 44 is not required. It will be understood that in an application such as this the tubular guide portion 24 of the tum buckle will be proportioned to receive the rigid shank; V

inaclose fitting sliding relationship as is the tubular sleeve portion 44 in the embodiments previously illus trated. Whereas it is preferred that the tubular sleeve section 44 be removable from the tubular guide section 24 so that the components of the jacking post may be taken apart to the shortest possible length. It will be understood that the tubular sleeve section 44 may be se cured to the tubular guide section 24 by welding or the i like if required.

From the foregoing it willbe apparent that the present invention provides a jacking post which can be eas ily adjusted in length by the selection of rigid shanks 48 of various lengths. In addition, the postis strengthened by the provision of a tubular guide section of a substantial length extending coaxially with respect to the rigid shank 48. These and other advantages of the jacking post of the present: invention will be apparent to those skilled in the art.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined asfollows:

1. A jack post comprising a. a tubular base section having a longitudinal axis,

b. a nut with a threaded through opening formed therein, c. mounting means for mounting said nut :in a position resting on one end of said base section with said threaded through opening thereof aligned with r the longitudinal axis of said base section, d. a threaded stem threadedly engaging said threaded opening of said nut;

V and the upwardly extending portion being disposed in a close fitting relationship about said elongated sleeve to contain said sleeve and thereby retain said rigid shank in aligned driving engagement with said threaded stem whereby rotation V of said nutl with respect to said threaded stem causes longitudinal movement of said e. a rigid shank resting onand'projecting upwardlyy' from said stern, f. a tubular guide section supported by said nut and adapted to contain andguide said rigid shank in, a aligned driving engagement with'said threaded stem whereby rotation of said nut with respect to 7 said threaded stern causeslongitudinal movement of said shank with respect to said tubular base. 2.. A jackpost as claimed in claim 1 including an elongated sleeve disposed coaxially with respect to and between said rigid shank and said tubular guide portion and projecting outwardly from said tubular; guide pork tion a substantial distance to laterally restrain said rigid shank.

3. A jack post as claimed in claim 1 including com-' A pression spring means disposedbetween said stem and" 1 said rigid shaft,said compression spring means being 1 compressedwhen said rigid shank is driven into engagement with a'load.

4. A jack post comprising, a tubular base, section having an upper endiface and a lower end face and a longitudinal axis extending between said end faces, a nut having a pair of oppositely disposed end faces, said nut beingrproportioned such that a first of said end faces shank being supported by said head of said stern for longitudinal movement therewith, an elongated sleeve disposed coaxially with respect to said rigid shank and i having a lower end resting on the otherend face of said nut, said elongated sleeve projecting upwardly from said nut a substantial distance to laterally. restrain said, I

rigid shaft, a tubular guide section mounted on said nut and projecting upwardly and downwardly from said nut, the downwardly extending portionbeing disposed in a close fitting relationship aboutsaid base section shank with respect to said tubular base. 

1. A jack post comprising a. a tubular base section having a longitudinal axis, b. a nut with a threaded through opening formed therein, c. mounting means for mounting said nut in a position resting on one end of said base section with said threaded through opening thereof aligned with the longitudinal axis of said base section, d. a threaded stem threadedly engaging said threaded opening of said nut, e. a rigid shank resting on and projecting upwardly from said stem, f. a tubular guide section supported by said nut and adapted to contain and guide said rigid shank in aligned driving engagement with said threaded stem whereby rotation of said nut with respect to said threaded stem causes longitudinal movement of said shank with respect to said tubular base.
 2. A jack post as claimed in claim 1 including an elongated sleeve disposed coaxially with respect to and between said rigid shank and said tubular guide portion and projecting outwardly from said tubular guide portion a substantial distance to laterally restrain said rigid shank.
 3. A jack post as claimed in claim 1 including compression spring means disposed between said stem and said rigid shaft, said compression spring means being compressed when said rigid shank is driven into engagement with a load.
 4. A jack post comprising, a tubular base section having an upper end face and a lower end face and a longitudinal axis extending between said end faces, a nut having a pair of oppositely disposed end faces, said nut being proportioned such that a first of said end faces rests on said upper end of said tubular base section, said nut Having a threaded through opening formed therein aligned with said longitudinal axis of said base section, a threaded stem threadably engaging said opening of said nut, said threaded stem having a head portion disposed above said nut, a rigid shank having a lower end and an upper end, the lower end of said shank being supported by said head of said stem for longitudinal movement therewith, an elongated sleeve disposed coaxially with respect to said rigid shank and having a lower end resting on the other end face of said nut, said elongated sleeve projecting upwardly from said nut a substantial distance to laterally restrain said rigid shaft, a tubular guide section mounted on said nut and projecting upwardly and downwardly from said nut, the downwardly extending portion being disposed in a close fitting relationship about said base section and the upwardly extending portion being disposed in a close fitting relationship about said elongated sleeve to contain said sleeve and thereby retain said rigid shank in aligned driving engagement with said threaded stem whereby rotation of said nut with respect to said threaded stem causes longitudinal movement of said shank with respect to said tubular base. 